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I posted a couple days ago...but what happened was that I took a big valve head, hybrid turbo, front mount IC, ported lower intake, gutted upper intake and put it on my 88 TC. I got it all back together, but the damn thing is so noisy, more so with advanced timing. If you disconnect the SPOUT, the noise goes away a lot, but you can still hear it. I have it timed right, cam timing is right on the money. Ignition timing is 10. When I rev it up the engine sounds like a mechanical knock, like a rod knock or something. If you drive it....WHAT THE HELL IS THAT?!? that's what youd say. The noise is so harsh it rattles the car, seats, shifter, etc. I can't figure it out. Compression is about 135-140 on all cylinders. Fuel pressure is about 44 psi. Vacuum is about 10 inches at idle. It does have a big cam though, it has a Modern Performance .520 lift, that may be the cause of the knock. It has Modern Perf big valve head, stock shortblock 120k miles, T3/To4e 54 trim, Grand national intercooler, gutted upper, ported lower, removed EGR valve, tube, and solenoid, Bob big log header. The head, turbo cam directly off of my other car which ran GREAT with no problem at all (except ring blowby). My 88 TC had no engine problems at all before, never smoked, good compression. I put everything onto my 88 TC and now I'm having this knock problem. I also have VERY LOW OIL PRESSURE. When you start it up cold it idles at about 30-40 psi. As soon as it gets warm and you drive it a little, oil pressure goes down about 15-20. But....it also goes as low as 5 PSI!
Yesterday I tore apart the engine again to see what I could find. The head gasket was NOT on upside down. The oil pump pumps up pretty good I only have to turn the distributor gear a couple notches before it starts to spit oil. The pistons have a little play in them, but not much at all, not near as bad as my 86 TC which had blowby. The bottom end looks like its in good shape. I can't see any reason why the oil pressure would be so low. I did find some lifters that were wore, so I replaced all the lifters with ones from my old head, that got rid of some lifter taps I had, but the loud knock is still there. I have yet to look at the cam bearings, but other than that I can't find any reason why the oil pressure would be so low. What else could cause low oil pressure?
Even if the oil pressure is low for some reason, if I fixed that....I don't think it would cure the knock. Because even when I start the car cold, and its got like 40 psi oil pressure, It still knocks and shit. I don't know whether its a mechanical knock, or a spark knock. I ran codes and got nothing out of the ordinary....KS code and EGR. I swapped in different plugs/cap/rotor, no change. I can't find any noticeable vacuum leak...although I haven't did a carb spray check yet.
The only thing I did this time around was I put in the distributor from the 86 (it was a different part numer printed on the label on the distributor).
I've tried messing with the timing and backing it off to see if it goes away, the more retarded it is, the less you hear the noise, but even retarded way down to like TDC or lower than that, you still hear it LOUD and of course its still not driveable. The 86 does have a PE Computer, which my 88 does not. Other than that, there is no difference in anything else...besides the ACT sensor in the 88 harness.
Before I swapped heads, my 88 TC would get like 40 psi at idle, at WOT or revving it up, I would go to like 50 or so. I don't know whether its something in the head or not. The only other thing I did after replacing the head was changing the oil. I sprayed alot of carb spray onto the engine to clean out the head bolt holes and alot of it went into the oil probably. WHen I got it all back together I ran it like like that for about 20 minutes, then I changed the oil/filter, used 10w30 like normal.
What causes low oil pressure? What can I check, I need help because I'm running out of ideas.
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1988 TurboCoupe - 5 Speed - 115k miles - Fully Loaded except Leather
5"x8" K&N in fenderwell, SVO T3 watercooled .63/.60 A/R, Gillis Valve @ 18 psi, Gutted Upper Intake, Ported/Profiled Lower Intake, Cleaned/Flowmatched Stock Injectors, HKS Super Sequential BOV, Walbro 255 HP Fuel Pump, Kirban AFPR, Bob's Big Log Header, 3" DP, No Cat, Dual 2.5" UltraFlos into ATR SS axle/tailpipes, Centerforce Dual Friction Clutch, Pro 5.0 Shifter, Koni Adjustable Struts, KYB Gas-A-Just Rear Shocks and Quads, Custom Progressive Rate 1" Lowering Springs, M.M. C/C Plates, Energy Suspension Parts Everywhere, PST Ball Joints/Tie Rod Ends, Various Autometer Phantom Gauges
Yesterday I tore apart the engine again to see what I could find. The head gasket was NOT on upside down. The oil pump pumps up pretty good I only have to turn the distributor gear a couple notches before it starts to spit oil. The pistons have a little play in them, but not much at all, not near as bad as my 86 TC which had blowby. The bottom end looks like its in good shape. I can't see any reason why the oil pressure would be so low. I did find some lifters that were wore, so I replaced all the lifters with ones from my old head, that got rid of some lifter taps I had, but the loud knock is still there. I have yet to look at the cam bearings, but other than that I can't find any reason why the oil pressure would be so low. What else could cause low oil pressure?
Even if the oil pressure is low for some reason, if I fixed that....I don't think it would cure the knock. Because even when I start the car cold, and its got like 40 psi oil pressure, It still knocks and shit. I don't know whether its a mechanical knock, or a spark knock. I ran codes and got nothing out of the ordinary....KS code and EGR. I swapped in different plugs/cap/rotor, no change. I can't find any noticeable vacuum leak...although I haven't did a carb spray check yet.
The only thing I did this time around was I put in the distributor from the 86 (it was a different part numer printed on the label on the distributor).
I've tried messing with the timing and backing it off to see if it goes away, the more retarded it is, the less you hear the noise, but even retarded way down to like TDC or lower than that, you still hear it LOUD and of course its still not driveable. The 86 does have a PE Computer, which my 88 does not. Other than that, there is no difference in anything else...besides the ACT sensor in the 88 harness.
Before I swapped heads, my 88 TC would get like 40 psi at idle, at WOT or revving it up, I would go to like 50 or so. I don't know whether its something in the head or not. The only other thing I did after replacing the head was changing the oil. I sprayed alot of carb spray onto the engine to clean out the head bolt holes and alot of it went into the oil probably. WHen I got it all back together I ran it like like that for about 20 minutes, then I changed the oil/filter, used 10w30 like normal.
What causes low oil pressure? What can I check, I need help because I'm running out of ideas.
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1988 TurboCoupe - 5 Speed - 115k miles - Fully Loaded except Leather
5"x8" K&N in fenderwell, SVO T3 watercooled .63/.60 A/R, Gillis Valve @ 18 psi, Gutted Upper Intake, Ported/Profiled Lower Intake, Cleaned/Flowmatched Stock Injectors, HKS Super Sequential BOV, Walbro 255 HP Fuel Pump, Kirban AFPR, Bob's Big Log Header, 3" DP, No Cat, Dual 2.5" UltraFlos into ATR SS axle/tailpipes, Centerforce Dual Friction Clutch, Pro 5.0 Shifter, Koni Adjustable Struts, KYB Gas-A-Just Rear Shocks and Quads, Custom Progressive Rate 1" Lowering Springs, M.M. C/C Plates, Energy Suspension Parts Everywhere, PST Ball Joints/Tie Rod Ends, Various Autometer Phantom Gauges